Can screen resolution be set in Active Directory Domain Group Policy?
There is no direct option for doing this in group policy.
What you can do though is write a startup script to do this for you and assign that out via group policy. You'll have to rely on a third party application to change the resolution. I did this once before and was able to find a free one. On my (very quick) search right now, I was only able to come up with this option.